Young children who exhibit difficulties with social-emotional, behavioral, and gross motor development in the early years face elevated risk for emotional and physical health problems in later childhood and adolescence. This compounded risk can be exacerbated further by adverse conditions associated for example with poverty. From a prevention perspective, there is a need for integrative interventions to address multiple critical developmental processes (e.g., gross motor development and social-emotional adjustment) in early childhood as these factors are established precursor for physical, behavioral, and emotional health. This study will investigate the immediate and sustained effects of an integrative intervention on social-emotional, behavioral, and gross motor development in preschool-age children from predominantly low-SES households. The intervention combines a classroom program, focused on promoting positive behavior and social interactions, with a gross motor skills training program, and tests it in a randomized controlled design. The specific aims are to: 1) examine the immediate post-intervention effect of the integrative intervention, compared with the control condition, on social-emotional, behavioral, and gross motor outcomes in preschool-age children; 2) evaluate six-month follow-up impact of the intervention (compared with controls) on the same outcomes, controlling for baseline levels; and 3) explore the moderating effects of baseline social-cognitive skills (e.g., executive function, working memory, self-regulation) on post-intervention effects. It is hypothesized that children exposed to the integrative intervention, compared with controls, will demonstrate higher levels of social-emotional and behavioral adjustment, and gross motor skills, at post-intervention and six-month follow-up assessments. The study tests the intervention with a sample of ?360 children (approximately 50% female) in Title 1 pre- Kindergarten classrooms located in a rural community in relative proximity to a metropolitan area. Data will be collected on: a) social-emotional and behavioral skills, b) gross motor skill competence and c) process assessments regarding all intervention fidelity and control group integrity (via systematic observation). Positive outcomes for the early childhood integrative intervention will add to the proposition that these kinds of prevention strategies are likely to bolster children?s overall healthy development.